diff --git a/reactos/include/wine/debug.h b/reactos/include/wine/debug.h
index 875396bb24d..3af86979922 100644
--- a/reactos/include/wine/debug.h
+++ b/reactos/include/wine/debug.h
@@ -37,6 +37,7 @@ struct _GUID;
 extern const char *wine_dbgstr_an( const char * s, int n );
 extern const char *wine_dbgstr_wn( const wchar_t *s, int n );
 extern const char *wine_dbgstr_guid( const struct _GUID *id );
+extern const char *wine_dbgstr_longlong( unsigned long long ll );
 extern const char *wine_dbg_sprintf( const char *format, ... );
 
 inline static const char *debugstr_an( const char * s, int n ) { return wine_dbgstr_an( s, n ); }
diff --git a/reactos/lib/libwine/debug.c b/reactos/lib/libwine/debug.c
index 9fb3e02ffe4..8862862fcfe 100644
--- a/reactos/lib/libwine/debug.c
+++ b/reactos/lib/libwine/debug.c
@@ -25,6 +25,7 @@
 
 #include <wine/config.h>
 #include <wine/port.h>
+#include <wine/debug.h>
 
 /* ---------------------------------------------------------------------- */
 
@@ -203,6 +204,12 @@ const char *wine_dbgstr_guid(const GUID *id)
     return str;
 }
 
+const char *wine_dbgstr_longlong( unsigned long long ll )
+{
+    if (ll >> 32) return wine_dbg_sprintf( "%lx%08lx", (unsigned long)(ll >> 32), (unsigned long)ll );
+    else return wine_dbg_sprintf( "%lx", (unsigned long)ll );
+}
+
 /* varargs wrapper for __wine_dbg_vsprintf */
 const char *wine_dbg_sprintf( const char *format, ... )
 {